package itheima.zuoye.test5;

public class Computer  {
    public void statup (){
        System.out.println("开机");
    }

    public void shutdown (){
        System.out.println("关机");
    }

    public void useDevice(USB usb){
        usb.open();
    }

    public void stopUsingDevice(USB usb){
        usb.close();
    }

    }

